Correlation of the structure and the luminescence properties of Eu~(3+)-doped Gd_2O_3 oxide between fiber single crystal and the nano-size powders

摘要

Gd_(2-x)Eu_xO_3 powder materials doped with Eu~(3+) using different concentration from x = 0 to 2 were prepared by a new sol-lyophilization synthesis and fiber single crystal (Gd_2O_3-Gd_2O_3/Eu~(3+)) oxides were grown using laser-heated pedestal growth (LHPG) technique. X-ray powder diffraction performed at room temperature showed that the materials obtained by lyophilization technique are cubic, lies in the nanometer range and different from bulk materials. The materials are a continued solid solution and the lattice parameter a-axis increases with Eu~(3+) concentration. The fibers grown by LHPG technique were single crystal, transparent, red in color when Eu~(3+) concentration is high, and the structure is monoclinic for Eu~(3+) < 15%. The luminescence of Eu~(3+) from C_2 crystallographic site was been detected. In the case of nano-particles oxide, an additional peak in emission spectral is obtained at λ = 610 nm. The influence of Eu~(3+), particles sizes and the structure on the luminescence spectral of Eu~(3+) ions was been described.